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How interface report data is calculated

Interface report data is calculated using the following formulas:

Interface Traffic :

This refers to the amount of data transmitted or received via the interface at a given point of time (bits per second).

In Traffic(bps): Rx Traffic: Delta_InOctets*8*1000/deltatime

Out Traffic(bps): Tx Traffic: Delta_OutOctets*8*1000/deltatime

Example:

Lets consider thee deltatime to be 15 minutes (900 seconds = 900000 milliseconds).
InOctets taken at the 1st poll (0th Minute)= 1000
InOctets taken at the 2nd poll (15th Minute)= 2000
So, Rx traffic = ((2000-1000)*8*1000) /900000 = 8.9 Mbps

InOctets (bytes) The difference between two ifInOctets collected at subsequent polls.
OutOctets(bytes) The difference between two ifOutOctets collected at subsequent polls.
ifInOctets (bytes).1.3.6.1.2.1.2.2.1.10The total number of octets received on the interface, including framing characters.
ifOutOctets(bytes).1.3.6.1.2.1.2.2.1.16The total number of octets transmitted out of the interface, including framing characters.
deltatime Time difference between two polls in milliseconds.
Note:
1. Multiplying by 8 is for converting bytes to bits.
2. Multiplying by 1000 is for converting 'per millisecond' to 'per second'.
3. The values mentioned in the above formulas are (InOctets, OutOctets) are the difference between two ifOctets values and not raw values.

Interface Utilization :

This refers to the Network traffic / interface speed at a given point of time in percentage.

In Utilization(%): (InTraffic/Inspeed)*100 = (Delta_InOctets*8*1000*100/deltatime*inspeed)
Out Utilization(%): (OutTraffic/OutSpeed)*100 = (Delta_OutOctets*8*1000*100/deltatime*Outspeed)

InOctets (bytes) The difference between two ifInOctets collected at subsequent polls.
OutOctets(bytes) The difference between two ifOutOctets collected at subsequent polls.
ifInOctets (bytes).1.3.6.1.2.1.2.2.1.10The total number of octets received on the interface, including framing characters.
ifOutOctets(bytes).1.3.6.1.2.1.2.2.1.16The total number of octets transmitted out of the interface, including framing characters.
deltatime Time difference between two polls.
Inspeed/ifSpeed.1.3.6.1.2.1.2.2.1.5An estimate of the interface\s current bandwidth in bits per second. (Can be defined by user).
Outspeed/ifSpeed.1.3.6.1.2.1.2.2.1.5An estimate of the interface\s current bandwidth in bits per second. (Can be defined by user).

Packets :

This refers to the total number of packets transmitted or received per second.

Rx Packets = (INUCAST + INDISCARDS + INERRORS + INUNKNOWNPROTOS + HCINMCAST + HCINBCAST)*1000/ deltatime

Tx Packets = (OUTUCAST + HCOUTMCAST + HCOUTBCAST)*1000/deltatime

InErrors.1.3.6.1.2.1.2.2.1.14The number of inbound packets that contained errors preventing them from being deliverable to a higher-layer protocol.
INUCAST.1.3.6.1.2.1.2.2.1.11The number of subnetwork-unicast packets delivered to a higher-layer protocol.
OUTUCAST.1.3.6.1.2.1.2.2.1.17The total number of packets that higher-level protocols requested be transmitted to a subnetwork-unicast address, including those that were discarded or not sent.
INDISCARDS.1.3.6.1.2.1.2.2.1.13The number of inbound packets which were chosen to be discarded even though no errors had been detected to prevent their being deliverable to a higher-layer protocol. One possible reason for discarding such a packet could be to free up buffer space.
INUNKNOWNPROTOS.1.3.6.1.2.1.2.2.1.15The number of packets received via the interface which were discarded because of an unknown or unsupported protocol.
HCINMCAST.1.3.6.1.2.1.31.1.1.1.8The number of packets, delivered by this sub-layer to a higher (sub-)layer, which were addressed to a multicast address at this sub-layer. For a MAC layer protocol, this includes both Group and Functional addresses. This object is a 64-bit version of ifInMulticastPkts.
HCOUTMCAST.1.3.6.1.2.1.31.1.1.1.12The total number of packets that higher-level protocols requested be transmitted, and which were addressed to a multicast address at this sub-layer, including those that were discarded or not sent. For a MAC layer protocol, this includes both Group and Functional addresses. This object is a 64-bit version of ifOutMulticastPkts.
HCINBCAST.1.3.6.1.2.1.31.1.1.1.9The number of packets, delivered by this sub-layer to a higher (sub-)layer, which were addressed to a broadcast address at this sub-layer. This object is a 64-bit version of ifInBroadcastPkts.
HCOUTBCAST.1.3.6.1.2.1.31.1.1.1.13The total number of packets that higher-level protocols requested be transmitted, and which were addressed to a broadcast address at this sub-layer, including those that were discarded or not sent. This object is a 64-bit version of ifOutBroadcastPkts.

Error Rate :

Error rate is the ratio between total number of Error packets and the total number of packets transmitted and received in percentage. It is calculated using SNMP interface OIDs like InErrors and OutErrors.

 

32-bit:

(InErrors+OutErrors)*100/(INUCAST + OUTUCAST + INDISCARDS + OUTDISCARDS + INERRORS + OUTERRORS + INUNKNOWNPROTOS + HCINBCAST + HCOUTBCAST)

64-bit:

 

 

(InErrors+OutErrors)*100/(INUCAST + OUTUCAST + INDISCARDS + OUTDISCARDS + INERRORS + OUTERRORS + INUNKNOWNPROTOS + HCINMCAST + HCOUTMCAST + HCINBCAST + HCOUTBCAST)

InErrors.1.3.6.1.2.1.2.2.1.14The number of inbound packets that contained errors preventing them from being deliverable to a higher-layer protocol.
OutErrors.1.3.6.1.2.1.2.2.1.20The number of outbound packets that could not be transmitted because of errors.
INUCAST.1.3.6.1.2.1.2.2.1.11The number of subnetwork-unicast packets delivered to a higher-layer protocol.
OUTUCAST.1.3.6.1.2.1.2.2.1.17The total number of packets that higher-level protocols requested be transmitted to a subnetwork-unicast address, including those that were discarded or not sent.
INDISCARDS.1.3.6.1.2.1.2.2.1.13The number of inbound packets which were chosen to be discarded even though no errors had been detected to prevent their being deliverable to a higher-layer protocol. One possible reason for discarding such a packet could be to free up buffer space.
OUTDISCARDS.1.3.6.1.2.1.2.2.1.19The number of outbound packets which were chosen to be discarded even though no errors had been detected to prevent their being transmitted. One possible reason for discarding such a packet could be to free up buffer space.
INUNKNOWNPROTOS.1.3.6.1.2.1.2.2.1.15The number of packets received via the interface which were discarded because of an unknown or unsupported protocol.
INNUCAST.1.3.6.1.2.1.2.2.1.12The number of non-unicast (i.e., subnetwork- broadcast or subnetwork-multicast) packets delivered to a higher-layer protocol.
OUTNUCAST.1.3.6.1.2.1.2.2.1.18The total number of packets that higher-level protocols requested be transmitted to a non- unicast (i.e., a subnetwork-broadcast or subnetwork-multicast) address, including those that were discarded or not sent.
HCINMCAST.1.3.6.1.2.1.31.1.1.1.8The number of packets, delivered by this sub-layer to a higher (sub-)layer, which were addressed to a multicast address at this sub-layer. For a MAC layer protocol, this includes both Group and Functional addresses. This object is a 64-bit version of ifInMulticastPkts.
HCOUTMCAST.1.3.6.1.2.1.31.1.1.1.12The total number of packets that higher-level protocols requested be transmitted, and which were addressed to a multicast address at this sub-layer, including those that were discarded or not sent. For a MAC layer protocol, this includes both Group and Functional addresses. This object is a 64-bit version of ifOutMulticastPkts.
HCINBCAST.1.3.6.1.2.1.31.1.1.1.9The number of packets, delivered by this sub-layer to a higher (sub-)layer, which were addressed to a broadcast address at this sub-layer. This object is a 64-bit version of ifInBroadcastPkts.
HCOUTBCAST.1.3.6.1.2.1.31.1.1.1.13The total number of packets that higher-level protocols requested be transmitted, and which were addressed to a broadcast address at this sub-layer, including those that were discarded or not sent. This object is a 64-bit version of ifOutBroadcastPkts.

Discard Rate:

Discard rate is the total number of Discarded packets / total number of packets transmitted and received in percentage.

32-bit :

(InDiscards+OutDiscards)*100/(INUCAST + OUTUCAST + INDISCARDS + OUTDISCARDS + INERRORS + OUTERRORS + INUNKNOWNPROTOS + HCINBCAST + HCOUTBCAST)

64-bit :>

 

 

(InDiscards+OutDiscards)*100/(INUCAST + OUTUCAST + INDISCARDS + OUTDISCARDS + INERRORS + OUTERRORS + INUNKNOWNPROTOS + HCINMCAST + HCOUTMCAST + HCINBCAST + HCOUTBCAST)

 

InErrors.1.3.6.1.2.1.2.2.1.14The number of inbound packets that contained errors preventing them from being deliverable to a higher-layer protocol.
OutErrors.1.3.6.1.2.1.2.2.1.20The number of outbound packets that could not be transmitted because of errors.
INUCAST.1.3.6.1.2.1.2.2.1.11The number of subnetwork-unicast packets delivered to a higher-layer protocol.
OUTUCAST.1.3.6.1.2.1.2.2.1.17The total number of packets that higher-level protocols requested be transmitted to a subnetwork-unicast address, including those that were discarded or not sent.
INDISCARDS.1.3.6.1.2.1.2.2.1.13The number of inbound packets which were chosen to be discarded even though no errors had been detected to prevent their being deliverable to a higher-layer protocol. One possible reason for discarding such a packet could be to free up buffer space.
OUTDISCARDS.1.3.6.1.2.1.2.2.1.19The number of outbound packets which were chosen to be discarded even though no errors had been detected to prevent their being transmitted. One possible reason for discarding such a packet could be to free up buffer space.
INUNKNOWNPROTOS.1.3.6.1.2.1.2.2.1.15The number of packets received via the interface which were discarded because of an unknown or unsupported protocol.
INNUCAST.1.3.6.1.2.1.2.2.1.12The number of non-unicast (i.e., subnetwork- broadcast or subnetwork-multicast) packets delivered to a higher-layer protocol.
OUTNUCAST.1.3.6.1.2.1.2.2.1.18The total number of packets that higher-level protocols requested be transmitted to a non- unicast (i.e., a subnetwork-broadcast or subnetwork-multicast) address, including those that were discarded or not sent.
HCINMCAST.1.3.6.1.2.1.31.1.1.1.8The number of packets, delivered by this sub-layer to a higher (sub-)layer, which were addressed to a multicast address at this sub-layer. For a MAC layer protocol, this includes both Group and Functional addresses. This object is a 64-bit version of ifInMulticastPkts.
HCOUTMCAST.1.3.6.1.2.1.31.1.1.1.12The total number of packets that higher-level protocols requested be transmitted, and which were addressed to a multicast address at this sub-layer, including those that were discarded or not sent. For a MAC layer protocol, this includes both Group and Functional addresses. This object is a 64-bit version of ifOutMulticastPkts.
HCINBCAST.1.3.6.1.2.1.31.1.1.1.9The number of packets, delivered by this sub-layer to a higher (sub-)layer, which were addressed to a broadcast address at this sub-layer. This object is a 64-bit version of ifInBroadcastPkts.
HCOUTBCAST.1.3.6.1.2.1.31.1.1.1.13The total number of packets that higher-level protocols requested be transmitted, and which were addressed to a broadcast address at this sub-layer, including those that were discarded or not sent. This object is a 64-bit version of ifOutBroadcastPkts.

Total Bytes Transferred :

This refers to the total number of bytes transferred and received in the interface.

Rx Bytes = INOCTETS

Tx Bytes = OUTOCTETS

Total Bytes = INOCTETS + OUTOCTETS

InOctets (bytes) The difference between two ifInOctets collected at subsequent polls.
OutOctets(bytes) The difference between two ifOutOctets collected at subsequent polls.
ifInOctets (bytes).1.3.6.1.2.1.2.2.1.10The total number of octets received on the interface, including framing characters.
ifOutOctets(bytes).1.3.6.1.2.1.2.2.1.16The total number of octets transmitted out of the interface, including framing characters.

Errors and Discards :

This refers to the total number of Error and Discard packets transmitted or received via the interface.

RxError = InErrors

TxError = INDISCARDS

RxDiscard = OutErrors

TxDiscard = OUTDISCARDS

InErrors.1.3.6.1.2.1.2.2.1.14The number of inbound packets that contained errors preventing them from being deliverable to a higher-layer protocol.
OutErrors.1.3.6.1.2.1.2.2.1.20The number of outbound packets that could not be transmitted because of errors.
INDISCARDS.1.3.6.1.2.1.2.2.1.13The number of inbound packets which were chosen to be discarded even though no errors had been detected to prevent their being deliverable to a higher-layer protocol. One possible reason for discarding such a packet could be to free up buffer space.
OUTDISCARDS.1.3.6.1.2.1.2.2.1.19The number of outbound packets which were chosen to be discarded even though no errors had been detected to prevent their being transmitted. One possible reason for discarding such a packet could be to free up buffer space.
 
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